DISLOCATION ARRANGEMENTS IN ALUMINUM DEFORMED IN TENSION OR BY FATIGUE
A comparison was made of transmission electron microscope observations on polycrystalline alumiuum deformed in tension or by fatigue. The dislocation distribution in aluminum deformed in tension was studied as a function of stress. At stresses up to 3 kg mm/sup-2/ the distribution is extremely irregular; at higher stresses up to the fracture stress, polygon boundaries are formed which become increasingly well developed with increasing stress. Observations were made on specimens fatigued at high stress, giving a life of 105 cycles, and low stress, giving a life greater than 108 cycles. The dislocation distribution in the former is similar to that in the unidirectionally deformed specimens. The low stress fatigue specimens show two new features. Firstly, polygonization does not occur despite a high dislocation density, and secondly, a high density of dislocation loops similar to that found in quenched specimens is observed in some areas. The latter observation suggests the formation of large numbers of point defects during fatigue. (auth)
- Research Organization:
- Cavendish Lab., Cambridge, Eng.
- Sponsoring Organization:
- USDOE
- NSA Number:
- NSA-14-001862
- OSTI ID:
- 4244469
- Journal Information:
- Phil. Mag., Journal Name: Phil. Mag. Vol. Vol: (8), 4
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
Similar Records
Plastic Behavior of a Nickel-Based Alloy under Monotonic-Tension and Low-Cycle-Fatigue Loading
Effects of shear stress component and loading path on fatigue strength under tension/torsion biaxial cyclic loading